Do EIFS deco band required to have slope away from structure

[RICHARD TAN]

Do EIFS Deco band required to slope away from structure?

[Jerry Peck - Codeman]

Hi Richard,

Complex answer to a simple question.

First, from the 2004 Florida Building Code, Residential with 2006 revisions. (underlining and bold are mine)
- R703.9 Exterior insulation finish systems, general.
- - All Exterior Insulation Finish Systems (EIFS) shall be designed or tested to meet the wind pressures specified in Table R301.2(2) and installed in accordance with the manufacturer’s approved installation instructions and the requirements of this section. Decorative trim shall not be face nailed through the EIFS. The EIFS shall terminate not less than 6 inches (152 mm) above the finished ground level.

From the Sto StoTherm Installation Guide, Failure Prevention starting on page 26.
- Failure Prevention
- - Moisture Intrusion and Critical Details
- - - Most moisture intrusion problems do not occur because of material failures. They occur because of poorly designed or constructed details that allow water to enter walls rather than direct water to the exterior. To avoid costly water intrusion problems a few simple principles must be followed in the detailing of the construction. Many of these details rely on flashing to make a leakproof transition between abutting construction elements.
- - - - (following are drawings for various details, including_
- - - - - 1. Sill flashing beneath window
- - - - - 2. Kick-out flashing at lower roof terminations
- - - - - 3. Sealant around windows & doors
- - - - - 4. Sealant at penetrations
- - - - - 5. Expansion at floor lines & sealant
- - - - - 6. Finish above grade
- - - - - 7. Head flashing above window
- - - - - 8. Flashing over buildouts (I will come back to this one)
- - - - - 9. Cap flashing over parapets
- - - - - 10. Saddle flashing at lower/higher walls
- - - - - 11. Flashing at decks
- - - - - 12. Protection of rough openings

Going back to 8. Flashing over buildouts. What is shown is "trim" or "buildout" of the EIFS from the plane of the wall. The drawing (limited in use to post here as it is a very rudimentary drawing with limited resolution) shows a through-wall flashing beginning at the back side of the upper EIFS area, extending the flashing down behind the upper EIFS panel and out over the "buildout" or "trim", with the outer edge of the flashing turned down similar to a drip edge metal with a turned out rain drip along its bottom edge.

With this being the installation instruction detail for Sto, one of the larger manufacturers of EIFS systems, and the code specifying that it is to be installed in accordance with the manufacturer's installation instructions, the manufacturer's installation instructions become code by reference and the detail shown become the proper and approved way to install "trim" or "buildouts" on Sto systems.

Being as most EIFS manufacturers use the same or similar installation instructions, I looked at the EIMA (EIFS Industry Members Association) Guide to EIFS Construction from 06/2000. The detail drawings in this guide are in must greater detail and resolution than in the Sto Installation Guide, but no detail showing "trim" or "buildouts", however, at the bottom of window sills it does show either a flashing or a 6:12 slope (which is 1:2 or 1 inch fall to 2 inches run).

Next I moved on to a different and newer guide from 06/2007, also from EIMA titled Guide to Exterior Insulation & Finish System Construction. This newer guide shows the same details as the earlier 06/2000 guide and also lacks any details for "trim" or "buildouts". It does show the same flashings or sloped sills below windows as the 06/2000 guide does.

For additional clarification I will need to wait until Monday when I can e-mail EIMA and ask for any details they have regarding "trim" or "buildouts".

Codeman

[Jerry Peck - Codeman]

Hi Richard,

This is the response I received back from my inquiry, and, yes, the top of the EIFS trim, whether installed on stucco or on EIFS systems, the top of trim and projecting architectural features is supposed to have a 1:2 slope, 1" down for each 2" projection.

(underlining and bold are mine for highlighting) Note: the reference to horizontal reveals is referring to the top of the EIFS below the reveal, i.e., such as the EIFS and/or trim below windows, etc.

Dear Mr. Peck:

The short answers to your questions are:

1) Yes, a 1:2 slope is recommended. From our specifications:
- G. Trim, Projecting Architectural Features and Reveals
- - 1. All trim and projecting architectural features must have a minimum 1:2 [27 degree] slope along their top surface. All horizontal reveals must have a minimum 1:2 [27 degree] slope along their bottom surface. Increase slope for northern climates to prevent accumulation of ice/snow and water on surface. Where trim/feature or bottom surface of reveal projects more than 2 inches (51 mm) from the face of the EIFS wall plane, protect the top surface with waterproof base coat. Periodic inspections and increased maintenance may be required to maintain surface integrity of EIFS on weather exposed sloped surfaces. Limit projecting features to easily accessible areas and limit total area to facilitate maintenance and minimize maintenance. Refer to Sto details 1.04a and 1.04b.
- - 2. Do not use EIFS on weather exposed projecting ledges, sills, or other projecting features unless supported by framing or other structural support and protected with metal coping or flashing. Refer to Sto detail 10.61.

2) No, Through wall flashing is not required in all cases. The detail to which you refer appears to be a schematic (No. 8). This is not a complete detail and the flashing is not actually "through-wall" it is only through the EIFS and tied into the water-resistive barrier at the sheathing surface. Flashing would be required if the intent is to drain the EIFS or stucco above in order to get the water to the outside face of the building. In uninterrupted EIFS or stucco with build-outs the flashing is not required if the minimum slope requirements are met and a waterproof base coat is used where required as called for in the specifications above.

3) These answers are appropriate for both EIFS and Stucco buildouts.

I am attaching a couple of details for your information. While there may be some variations between different manufacturers, the basics of these answers are consistent among us.

Regards,

Terry L. Viness, P.E.
Sr. Technical Service Manager
Sto Corp.

Tel: 404.346.3666
Fax: 404.346.7422
tviness@stocorp.com